Electrical switch gear



Filed Feb. 20, 1924 Z SIIQQtS-5h@t WITNESSES: I

ATTORNEY Oct. 22, 1929. T. c. CHRISTIANSON 1,732,713

ELECTRICAL SWITCH GEAR Filed Feb. 20. 1924 2 Sheets-Sheet 2 F/ig, 3.

INVENTOR Theodore C Omisf/omon ATTORNEY Patented Oct. 22, 1929 UNITED.STATES PATENT OFFICE THEODORE CHRISTIAN CHRISTIANSON, 0F MANCHESTER,ENGLAND, ASSIGNOB TO WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, ACORPORATION 01 PENNSYLVANIA ELECTRICAL SWITCH GEAR Application filedFebruary 20, 1924, Serial No.

My invention relates to electrical switch mechanisms and in particularto switch mechanisms of the kind or class wherein busbars, cables,contacts and other electrical conductors or devices are enclosed inmetal casings. Such switch mechanism is commonly known as armoured oriron-clad switch mechanism and comprises, in general, one or more oilswitches by means of which circuits carrying currents are made andbroken and one or more other switches, such as isolating or selectorswitches, which are emloyed for establishing various connections butwhich are not adapted for making or breaking circuits when carryingheavy currents.

c The object of the invention is to provide in a switch mechanism of thekind above set forth an improved construction and arrangement of switchof the latter class, that is to say, a switch which is not required tobreak a heavy current and which may be advantageously employed foreffecting alternative connections, such for instance, as is necessary incases where alternative sets of bus-bars are provided, or whereswitching means are required for ear-thing different parts of the switchgear, such as the bus-bars orthe cable as is sometimes required fortesting and other purposes. The improved switch may also be used for.eltecting other connections in the switch mechanism.

The improved switch, according to the invention is of the socket andmovable plug or plunger type and the plug is removable from its socket,access to the plug being obtained through an orifice in the armouring ormetal casing of the switch mechanism, the arrangement being such thatsaid plug 1s removable from the switch gear and may, if required, beinserted therein at another place to complete a different circuit havingsimilar terminals.

The invention may be employed with advantage in armoured switchmechanism of the type in which the oil circuit-breaker structure isnormally fixed to, but susceptible of separation from, the fixedarmoured structure housing, for instance, the bus-bars; it may also beemployed with advantage in the so-called draw-out or truck type ofswitch mechanism, that is to say, switch mechanism wherein one 694,023,and in Great Britain March 8, 1923.

portion thereof,'such as the oil switch and associated conductors, ismovable relative to another portion thereof, such as the chamber orchambers containing the bus-bars and other devices and whereinelectrical connection between the portions of the mechanism is effectedby means of isolating switches for instance, of the plug and sockettype, which are operated by movement of one of said p0r-' move the truckback again to its operative po- I sition and finally to close the oilswitch. In

other constructions, the contact members carried by the truck arearranged to connect, at all times, with both of the bus-bars andindependently operable selector switches are provided by which one orother of the truck contacts may-be connected wit-h the terminalof theoil switch. The employment of switches according to the presentinvention in switch mechanism of this type permits change of connectionfrom one bus-bar to the duplicate bus-bar to be made without moving thetruck from its operative position.

In order that the invention may be clearl understood it will now bedescribed with re -erence to the accompanying drawings as applied by wayof example, to switch gear of the draw-out type, wherein Fig. 1 is adiagrammatic vertical section through one phase of a three-phase switchmechanism; and

Fig. 2 is an electrical diagram of the circuit conneptions for theapparatus shown in Fig. 1 an Fig. 3 is an enlarged front elevationalview of the apparatus shown in Fig. 1.

Referring to Fig. 1, the apparatus includes mechanism containing thebus-bars, the sleeves 6, 7 and 8 project into sleeves 9, l0 and 11located in bus-bar and cable chambers 12, 13

and 14, constituting the stationary cell as.

shown in the drawing. The sleeves 9, 10 and 11 contain metallicterminals 15, 16 and 17 having sockets 18 19 and 20 which are coaxialwith corresponding holes 21, 22 and 23 formed in the annularcontacts 3,4 and 5.

The three terminals 15 corresponding to the three phases are connected,each with one of the bus-bars 24 located in the chamber 12, theterminals 16 being similarly connected with a duplicate set of bus-bars25 located in the chamber 13 while the terminals 17" are connected tothe three-phase conductors of a cable 26. The contact members 5 areconnected to three switch contact members 27 of A the oilcircuit-breakers 1, the phase contacts 28 of which are connected bothtothe contact members 3 and 4 as indicated by the conduc tors 31.

The phase terminals 15, 16 and 17 are adapted to be electricallyconnected to the corresponding phase contacts 3, 4 and 5, rev

s ectively, by means of the movable plugs 29.

ach of these plugs comprises a metallic rod having one end adapted tofit into one of the sockets 18, 19. or 20, the other end having, forinstance, a conical portion turned thereon which is adapted to fit intothe contacts 3, 4 and 5. i

An insulating handle 30. is provided by means of which a plug may beremoved from an operative position and, if required, inserted in anotheroperative position, it being unnecessary to open the truck for thispurpose since the handle 30 projects through an opening in the casing tothe exterior. The insulating handle 30 is turned preferably to nearlythesame diameter as the inside of sleeves 6, 7 and 8 in order to excludemoisture, dust and the like. Instead of providing a handle, the

lug may be connected by an insulating memher with a metal or otherexternal member and may be operated electrically or mechanically eltherdirectly 'or by remote control means, (not shown).

Plu 5 may also be provided of other type than t ose described above,adapted, to make connection between an external temporar circuit andanyone of the contacts 15, 16, 1 oriof 3, 4, 5, for such purposes astesting or earthing.

Referring to Fig. 2 the circuit connections are more clearly shown, thereference numerals indicating the same with reference to Fig. 1.

When it is desired to connect the cable 26 to one of the sets ofbus-bars 24 or 25 and the truck has been moved in its closed position,three plugs are so inserted as to electrically connect the terminals 5and 17, the three phase conductors of the feeder 26 being then connectedto the switch contacts 27 .of the oil switch 1. Three more plugs arethen inserted in either the terminals 3 and 15 or the terminals 4 and 16according to whether it is desired to connect the feeder cable 26 to thebus-bars 24 or the bus-bars 25. In the drawings, the plugs are shown asconnecting the terminals 15 and 3.

The oil switch 1 is then closed, whereupon the circuit is completed fromthe terminals 17 through the plugs 29, contacts 5, the switch contacts27 and 28 of the oil switch, conductors 31, contacts 3, plugs 29,terminals 15 and thence to the bus-bars 24. If it is desired afterwardsto connect the cable 26 to the busbars 25, the oil switch 1 is openedand the plugs are withdrawn from the terminals 3 and 15 and inserted inthe terminals 4 and 16 and the oil switch is then reclosed. By employingan interconnecting switch (not shown) to enable the bus-bars to betemporarily connected in parallel, it is possible, with the abovearrangement, to change over from one set of bus-bars to the other setwithout interrupting the power supply to the cable 26.

In order to prevent the removal or insertion of a plug while the oilswitch is closed, a suitable interlock may be provided between the oilswitch operating mechanism and the plugs. One form of such interlock isdiagrammatically illustrated in Fig. 1 by means of a plate 32 whichcannot be moved laterally into its open position to permit of theremoval or insertion of a plug until the member 33 fixed to and rotatingwith the operating shaft 34 of the oil switch mechanism is in a positioncorresponding to the open position parts described of the switchcontacts 27 and 28 as indicated in Fig. 2. 'Means may also be providedfor I preventing the plugs being simultaneously connected to two sets ofbus-bars at the same time. Thus, a shutter 35 may be provided which ismovable about a hinge 36 and is such that it can cover either theopenings into the sleeves '6 or the openings into the sleeves 7. Theshutter cannot be closed against the side of the oil switch hood 2 ifplugs are inserted in the contact members 3 and 4 simultaneously and itis not possible therefore to place the plate 32 in its closed positionwhich owing to the interlock member 33 in turn prevents the oil switchbeing closed.

Shutters, (not shown), may also be provided which will automaticallyshroud the entrances of the sleeves in the fixed part of' the switchgear whenthe' truck is removed and in the truck structure when the plugsare removed.

' Any preferred system of measuring instruments and of protection may beemployed in connection with the switch mechanism and improved plug andsocket switches in accordance with the invention may be convenientlymade use of in such a system.

Referring to Fig. 1, a current transformer for a current measuringinstrument is diagrammatically illustrated at 37 while conductors 38 areled to potential transformers for voltage measuring instruments. Fig. 2

shows clearly the connections for the voltage transformer which isindicated at 39, the circuit being conveniently completed a through aplug and socket switch 40 of the type described. I

Plug and socket switches in accordance with the invention may beemployed in ironclad switch mechanism, other than of the truck type andfor other purposes than those herein indicated such as for connectingthe various enclosed apparatus of the switch gear to earth or to testinginstruments, suitable sockets and corresponding orifices in thearmouring or casing bein provided so that by inserting one or more plugsor plungers into the appropriate socket any of such parts may beconnected to earth or elsewhere as required. I

In some cases, it is desirable to arrange that the withdrawal of a plugfrom a socket should take place under oil or other insulating liquid.This can readily be effected by arranging that the axes of the plugs andsockets shall be inclined to the horizontal so that the sockets formreceptacles for oil or other insulating liquid into which the plugs areinserted in a downward direction.

One advantage of the employment of the improved switch in iron-cladswitch mechanism having duplicate bus-bars or other connections ashereinbefore described is that it can readily be seen,.by inspection,which set of bus-bars is connected to the oil switch without thenecessity of opening the oil time. 1

In the case of selector switches more than two sets of bus-bars may beprovided and the bus-bar chambers may be located either all on one sideor some on one side and some on the other side of the oil switch. Insome cases a short plug connected to earth and adapted to makeconnection only with one or other or both of the terminals of the switch.may be employed when it is desired to effect the earthing of a bus-baror other conductor .connected to the switch terminal.

It will be understood that various modifications may be made in theconstruction of the improved switch as described and illustrated withoutdeparting from the scope of the invention.

I claim as my invention:

1. Switch mechanism comprising a pair of relatively movable terminalmembers having separate housings, and a plug member for connecting thesaid terminal members detachably connected to one terminal member andmovable into contact with the other terminal member and accessible foroperation from the front of the mechanism through an orifice in one ofthe housings.

2. Switch mechanism comprising a pair of relatively movable terminalmembers having separate housings, and a plug member for connecting thesaid terminal members detachably connected to one terminal member andmovable into contact with the other terminal member and accessible foroperation through an orifice in one of the housings.

3. Switch mechanism comprising a plurality of pairs of relativelymovable terminal members, and a plug member adapted to be selectivelysecured to a terminal of any pair of terminal members .and movable intocontact with the other terminal of the said pair of terminal members, acircuit breaker connected to one of the said terminal members and meansfor preventing disconnection of the said plug except when the circuitbreaker is in open position. 4. Switch mechanism comprising a pluralityof pairs of relatively movable terminal members and a plurality of plugmembers adapted to be selectively and detachably secured to terminals ofany of said pairs of terminal members and movable into contact with theother terminals of said pairs of terminal members, a circuit breakerconnected to one of the said terminal members. and means for preventingclosing of the circuit breaker so long as two or more plugs aresimultaneously secured to terminal members of certain pairs of terminalmembers.

5. The combination with a switch mecha- I nism having a fixed terminaland a circuit breaker having a terminal movable with respect to thefixed terminal, of a conductive plugdetachably connected to the movableterminal and movable into contact with the fixed terminal.

6. The combination-with a switch mechanisin having a plurality of fixedcontact terminals and a circuit breaker having a plurality of terminalsmovable with respect to the fixed terminals, of a conductive plug memberada ted to be detachably connected to any of the said movable terminalsand movable into contact with a selected contact terminal.

7. The combination with a switch mechanism having aplurality of fixedcontact ter minals and a circuit breaker having a plurality of terminalsmovable with respect to the fixed terminals, of a plurality ofconductive plug members adapted to be detachably connected to any of thesaid movable termi- 5 nals and movable into contact with selectedcontact terminals.

8. The combination with a switch mechanism having a plurality of fixedcontact terminals and a circuit breaker having a plum rality ofterminals movable with respect to the fixed terminals, of a conductiveplug member adapted to be detachably connected to any of the saidmovable terminals and movable into contact with a selected contactterminal and means for preventing disconnection of the plug membersexcept when the circuit breaker is in open position.

9. The combination with a switch mechanism having a plurality of fixedcontact terminals and a circuit breaker having a plurality of terminalsmovable with respect to the fixed terminals, of a plurality ofconductive plug members adapted to be detachably connected to any of thesaid movable terminals and means for preventing closure of the circuitbreaker so long as two or more plug members are connected to certain ofthe said movable terminals.

10. The combination with a switch mechanism having a fixed cell providedwith a con tact terminal and a movable circuit breaker device providedwith an enclosure containing a terminal member, of a conductive plugmember detachably secured to the-terminal member and accessible throughan orfice in the enclosure for connecting the terminal member to thecontact terminal.

11. Switch mechanism comprising a pair of relatively movable supportmembers, a

plurality of terminal members on each support member, and a connectingmember adapted to be selectively detachably connected to one of theterminal members on one support member and movable with the said supportmember into engagement with a selected terminal member on the othersupport member.

12. Switch mechanism comprising a pair of relatively movable supportmembers, a

53 plurality of terminal members on each support member, and aconnecting member adapted to be selectively detachably connected to oneof the terminal members on one support member for engaging a selectedterminal member on the other support member, the connecting member beingoperable from the outer side of the first said support member.

In testimony whereof, I have hereunto subscribed my name thistwenty-third day of January, 1924.

- THEODORE CHRISTIAN CHRISTIANSON.

